Method of measuring crop humidity in a harvester

Abstract

A method of assessing the humidity or moisture content of crop is provided for an agricultural harvester for use during harvesting operations. The method involves harvesting a field using a harvesting machine equipped with a moisture sensor for monitoring the moisture content of the harvested crop and a mass flow rate sensor for monitoring the mass flow rate of crop material in the harvesting machine. The raw moisture data derived from the signal of the moisture sensor are combined with the mass flow rate data for establishing the actual moisture content of the crop material. This moisture data can be used to establish a moisture content map for the field, which has the advantage of identifying field spots with weed infection.

Having thus described the invention, what is claimed is:  
     
       1. A method for assessing the humidity of a crop during harvesting operations, comprising the steps of: 
       harvesting a field using a harvesting machine which includes:  
       a mechanism for collecting crop from the field and feeding it into said harvesting machine;  
       a mechanism for processing said crop fed into said harvesting machine;  
       a moisture sensor for monitoring the moisture content of the collected crop and generating a signal; and  
       a mass flow rate sensor for monitoring the mass flow rate of crop material in said harvesting machine and generating a signal;  
       logging data from said moisture sensor and said mass flow rate sensor while harvesting the field; and  
       deriving the actual moisture content of the collected crop from the combined data from said moisture sensor and from said mass flow rate sensor by the substeps of:  
       monitoring the signal from the moisture sensor and deriving therefrom a raw moisture content value;  
       monitoring the signal from the mass flow rate sensor and deriving therefrom a mass flow rate value; and  
       adjusting the raw moisture content value inversely proportionally to the mass flow rate value to obtain the actual moisture content value by dividing the raw moisture content value by a factor.  
     
     
       2. The method of claim  1  wherein said 
       factor is linearly proportional to the mass flow rate value.  
     
     
       3. The method of claim  2  wherein said harvesting machine further includes a location device for locating the position of said harvesting machine in the field, said method further comprising the steps of: 
       logging data from said location device while harvesting said field; and  
       establishing a map representative of the derived moisture content at several locations in said field based on said logged data.  
     
     
       4. The method of claim  3  wherein said map establishing step comprises the step of: 
       establishing a map showing locations where said derived moisture content exceeds a threshold level, thereby indicating of the presence of weed in the field.  
     
     
       5. The method of claim  4  wherein said moisture sensor monitors the conductivity of the crop fed into the harvesting machine. 
     
     
       6. The method of claim  5  wherein said moisture sensor includes at least one sensor plate mounted onto an insulating plate inside a conveyor housing of the harvesting machine and a means for measuring the electrical current flowing from said sensor plate, via the collected crop, to the conveyor housing. 
     
     
       7. The method of claim  6  wherein said mass flow rate sensor monitors the flow rate of the total crop collected by said crop collecting means. 
     
     
       8. The method of claim  6  wherein said mass flow rate sensor measures the amount of power used to drive a conveyor which transports the collected crop. 
     
     
       9. The method of claim  6  wherein said mass flow rate sensor monitors the flow rate of a portion of the crop collected by said crop collecting mechanism. 
     
     
       10. The method of claim  6  wherein said mass flow rate sensor measures the flow rate of grain harvested and processed from crop by said crop processing mechanism. 
     
     
       11. A method of detecting weed infestation of crops being harvested by a harvesting machine having a crop harvesting header for collecting crops from a field and feeding the collected crops into a crop processing mechanism that processes the collected crop comprising the steps of: 
       logging data from a moisture sensor for monitoring the moisture content of the collected crop and from a mass flow rate sensor for monitoring the mass flow rate of crop material fed into said harvesting machine while collecting crop from the field;  
       deriving the actual moisture content of the collected crop from the combined data from said moisture sensor and from said mass flow rate sensor;  
       logging data from a location device for locating the position of said harvesting machine in the field while collecting crop from said field; and  
       establishing a map showing locations where said derived moisture content exceeds a threshold level, thereby indicating of the presence of weed infestation in the collected crop.  
     
     
       12. The method of claim  11  wherein said deriving step includes the steps of 
       monitoring the signal from the moisture sensor and deriving therefrom a raw moisture content value;  
       monitoring the signal from the mass flow rate sensor and deriving therefrom a mass flow rate value; and  
       dividing the raw moisture content value by a factor which is proportional to the mass flow rate value.  
     
     
       13. The method of claim  12  wherein said moisture sensor includes a pair of opposing sensor plates mounted such that the collected crop is fed between said opposing sensor plates inside a conveyor housing of the harvesting machine, said step of logging data from a moisture sensor including the step of: 
       monitoring the conductivity of the crop fed into the harvesting machine by measuring the electrical current flowing between said sensor plates via the collected crop.  
     
     
       14. A method of measuring moisture content of crops being harvested by a harvesting machine having a crop harvesting header for collecting crops from a field and feeding the collected crops into a crop processing mechanism that processes the collected crop comprising the steps of: 
       monitoring the conductivity of the crop fed into the harvesting machine by a moisture sensor including at least one sensor plate mounted inside a conveyor housing of the harvesting machine;  
       logging data from said moisture sensor and from a mass flow rate sensor for monitoring the mass flow rate of crop material fed into said harvesting machine while collecting crop from the field;  
       monitoring the signal from the moisture sensor and deriving therefrom a raw moisture content value;  
       monitoring the signal from the mass flow rate sensor and deriving therefrom a mass flow rate value; and  
       dividing the raw moisture content value by a factor which is linearly proportional to the mass flow rate value; and  
       establishing a map representative of the derived moisture content at several locations in said field based on said logged data.  
     
     
       15. The method of claim  14  wherein said step of monitoring the conductivity of the crop includes the step of: 
       measuring the electrical current flowing from said sensor plate, via the collected crop, to the conveyor housing.  
     
     
       16. The method of claim  15  wherein said mass flow rate sensor measures the amount of power used to drive a conveyor which transports the collected crop. 
     
     
       17. The method of claim  15  wherein said step of establishing a map includes the step of: 
       showing on said map the locations where said derived moisture content exceeds a threshold level, thereby indicating of the presence of weed in the field.